The broad objective is to analyze the processes involved in the demographic transition, well underway in Taiwan. In considering factors immediately affecting fertility, how changes in marriage patterns affect fertility will be investigated, both to determine causes of later age at marriage and its effect on the number and spacing of children. In investigating the effects of breastfeeding, tests will be made of an earlier finding that breastfeeding after menstruation is resumed reduces fertility. Analysis for longer prospective periods will test earlier findings that family size preferences predict subsequent fertility more accurately than other predictors. Factors affecting fertility at the micro level will be investigated along several lines. Scales measuring the costs and benefits of children will be related to fertility. Changes from 1965 to 1976 in clusters of attitudes affecting fertility will be investigated to see which attitudes lag and which lead a change. A multivariate analysis of stratification variables affecting fertility will be done for specific recent birth and marriage cohorts. Whether size of family in one generation affects education, and thus fertility, in the next will be investigated for three linked generations. On the macro level, previous work on how the social-demographic characteristics of local areas affect fertility will be supplemented by newly available data on various aspects of agricultural development in local areas and by reproductive parameters for a sample of these areas, obtained by aggregating data from sample surveys. The data sources are all from published material or secondary analysis of surveys conducted by organizations in Taiwan and made available to us.